Boil the lentils in the water for 30 minutes over medium heat. Finely chop the onion, garlic and cilantro. Cut the tomatoes and bacon into small cubes. Sauté the onion and garlic in oil. Stir in cilantro and tomatoes and cook for 3 minutes. Add bacon to the lentils, reduce heat. Cook for 15 minutes more. Cut the banana into slices and fry in hot oil. Serve the lentils hot and serve with slices of banana. Season with salt to taste.